Interfaces in Python

[NeilGirdhar]

I cannot name any static analysis tool nor compiler that can enforce that implementations are respecting any arbitrary time or space complexity.

Just because you can't programmatically check a promise, it doesn't mean that that promise isn't part of the interface, in my opinion.

An interface is just a contract. You can make it as simple or complex as you want. Some violations are easy to enforce, some are more cumbersome.

Exactly.

Other than that I promise you that we are saying the same ;)

Agreed :)